1. Field of the Invention
This invention relates generally to packages and, more specifically, to packages useful for functionally coupling electronic components into a single electronic device.
2. Description of the Prior Art
In the past, electronic devices such as hand-held computers have been fabricated by methods incorporating a variety of hardware. One approach to packaging such devices was to mount all of the necessary electronic, manual input and sensory output devices on a single circuit board. Typical of such devices was a hand-held computer utilizing: a single printed circuit board mounting a display device having a display surface at an elevation from the printed circuit board; a matrix of key switches mounted on or very near the elevation of the printed circuit board; a case, mounting the printed circuit board, having an essentially flush surface at the elevation of the display surface; and a plurality of key caps to allow the actuation of the key switches from the flush surface. In addition to requiring additional passive parts in the form of key caps, such a method of construction presented a problem when attempting to seal the surface of the calculator against entry of foreign matter, particularly at those portions near the key caps.
An alternate method of constructing such hand-held calculator devices involved the use of a single printed circuit board mounting a display device having a display surface at a different elevation than the printed circuit board, a matrix of domed type key switches mounted proximal to the surface of the printed circuit board and sealed by an adhesive backed overlay, as illustrated by U.S. Pat. Nos. 4,042,439 and 4,085,306. Such a method of construction, however, left the surface of the keyboard surface at a different elevation than the display surface and thereby prevented the utilization of a single adhesive backed overlay to seal both the display surface framed by the display window in the case and the keyboard assembly.
An even further approach to manufacture of such a hand-held calculator device was to mount the display apparatus, and correspondingly the display surface, at a canted angle with respect to the plane of the keyboard surface and thereby provide improved visibility of the display surface to the operator. Such a method of construction, however, was accompanied by the corresponding cost problems associated with hard wiring the circuit boards to the display apparatus to provide an electrical connection.
A need existed for an electronic device package which would allow an operative electronic device having at least two printed circuit boards, each having a functional surface at a different elevation from the respective mounting surface of the printed circuit board, to be mounted to provide a single flush surface.